An Italian writer who had moved from Italy to the west coast of Scotland was asked why he had exchanged his glorious, sunny native land for those melancholy, rainy parts. “It is simple,” he replied. “In Italy, silence is very expensive. In Scotland, it is very cheap.”

Absolutely not. You don’t need one. It’s not going to change your world. If you’ve got a smart phone, this is a bit different, but not so much so that you’ll change the world with one. If you’re a writer, it’s really easy to justify this thing as a powerful focusing tool as I’m finding out from writing the new book. But need? Too big a word.

Not long ago, people who routinely plugged their own names into online search engines were thought to be engaging in “vanity Googling.” These days, it is an act of self-preservation. “Google yourself at least once a week,” advises Richard Levick, who heads a strategic communications firm in Washington, D.C. “You need to track what’s being said about you” on blogs, message boards and social-networking websites.

I noted that when the Economist magazine had three offers $59 for online only, $125 for print only, and $125 for both, 84% of purchasers chose the print-and-online option because they got the online for “free.” Nobody bought the $125 print-only option, and 16% went for the online-only offer. This meant that the “average basket” of the population of Economist shoppers was just over $114 84% of $125 + 16% of $59.When the print-only choice was removed, 68% of purchasers chose the $59 option, only 32% went for the print-and-online bundle, and the average basket was approximately $80 32% of $125 + 68% of $59. So when the decoy was added, the average sale increased from $80 to $114 dollars.